The invention relates generally to microreplication, and more particularly to tools used in a microreplication process.
Microreplication techniques can used to create a wide variety of microreplicated structures. Microreplicated structures are defined herein as structures that include features having at least one dimension smaller than 1000 microns. In one example, the features may form tapered protrusions that extend from a backing structure. In that case, the microreplicated structure may comprise one side of a mated surface fastener. For example, the mated surface fastener may include two microreplicated structures formed with tapered protrusions that extend from respective backing structures, and have cross-sectional widths smaller than 1000 microns. The protrusions may also collectively define an array of recesses. Thus, the two microreplicated structures can be pressed together such that the tapered protrusions mate with opposing recesses in an interlocking arrangement, thereby attaching the two microreplicated structures to one another.
Microreplication processes typically utilize microreplication tools such as a casting belt, a casting roller, an injection molding tool, or the like. For example, the microreplication tool may be used in an extrusion process or an injection molding process in which the microreplicated structures are created. The microreplication tool may include small cavities that define the microreplicated features of the microreplicated structure to be created. During the replication process, however, air entrapment within the cavities may undermine the quality of the microreplicated features. In other words, trapped air within the cavities of the microreplication tool may limit the ability of material being microreplicated to completely fill the cavities.
In general, the invention is directed to a microreplication tool that includes gas release features that allow gas to escape from microreplication cavities of the tool. Various embodiments may be directed to the microreplication tool, techniques for creating the tool, techniques for using the tool, and microreplicated structures created using the tool. The microreplication tool may comprise an extrusion tool, such as a casting belt or a casting roller, or an injection molding tool used for injection molding structures that define the small microreplicated features.
In one embodiment, a microreplication tool includes a set of cavities used to form microreplicated features during a microreplication process. The tool may also include gas release features disposed adjacent bottom regions of the respective cavities to allow gas to escape from the cavities during the microreplication process. In this manner, air entrapment within the cavities of the tool during the microreplication process can be avoided, thereby improving the quality of the microreplicated product.
Additional details of these and other embodiments are set forth in the accompanying drawings and the description below. Other features, objects and advantages will become apparent from the description and drawings, and from the claims.